1. Field of Invention
The present invention relates to a back cartridge structure, which is used in a handheld data processor, and more particularly to a back cartridge coupling structure that allows the body of the handheld data processor not to be scratched when the body and the back cartridge are jointed with each other.
2. Related Art
At present, the back cartridge is used to provide the handheld data processor with a sufficient electric power, it can be furnished a backup battery or other devices that can expand the function of the handheld data processor (such as CF, SD card receptacle module or wireless communication module). However, the coupling between the current back cartridge and the body of handheld data processor, such as Visor series products produced by Handspring, is achieved by an upward-faced connecter slot disposed in the body and a 90° projected, downward-faced connecter disposed on the back cartridge. The back cartridge must be slid face-to-face relative to the body in order for the connecter slot and connecter to be jointed when the back cartridge and the body are coupled. Therefore, the face of the back cartridge and the body will be scratched over a long period of time. Also, a relatively large gap must be maintained between the back cartridge and the body so that they can be slid smoothly. As a consequence, the back cartridge shakes easily after the coupling.
Therefore, it is important for us to invent a back cartridge coupling structure in order for the faces of the body of the handheld data processor and back cartridge not to scratch each other when they are coupled together.